Carotid Plaque Characteristics Research Articles

Characterization of carotid plaques using chemical exchange saturation transfer imaging.

The preoperative assessment of carotid plaques is necessary to render revascularization safe and effective. The aim of this study is to evaluate the usefulness of chemical exchange saturation transfer (CEST)-MRI, particularly amide proton transfer (APT) imaging as a preoperative carotid plaque diagnostic tool. We recorded the APT signal intensity on concentration maps of 34 patients scheduled for carotid endarterectomy. Plaques were categorized into group A (APT signal intensity ≥ 1.90 E-04; n = 12) and group B (APT signal intensity < 1.90 E-04; n = 22). Excised plaques were subjected to histopathological assessment and, using the classification promulgated by the American Heart Association, they were classified as intraplaque hemorrhage-positive [type VI-positive (tVI+)] and -negative [no intraplaque hemorrhage (tVI-)]. Of the 34 patients, 22 (64.7%) harbored tVI+- and 12 (35.3%) had tVI- plaques. The median APT signals were significantly higher in tVI+- than tIVI- patients (2.43 E-04 (IQR = 0.98-4.00 E-04) vs 0.54 E-04 (IQR = 0.14-1.09 E-04), p < .001). Histopathologically, the number of patients with tVI+ plaques was significantly greater in group A (100%, n = 12) than group B (45%, n = 22) (p < .01). The number of symptomatic patients or asymptomatic patients with worsening stenosis was also significantly greater in group A than group B (75% vs 36%, p < .01). In unstable plaques with intraplaque hemorrhage and in patients with symptoms or progressive stenosis, the ATP signals were significantly elevated. CEST-MRI studies has the potential for the preoperative assessment of the plaques' characteristics.

Correlation between the TyG-BMI index and carotid plaque characteristics in middle-aged and elderly patients with acute myocardial infarction.

The aim of this study is to investigate the correlation between the triglyceride-glucose-body mass index (TyG-BMI) and the characteristics of various carotid plaques in middle-aged and elderly patients with acute myocardial infarction (AMI). A retrospective study was conducted on 380 patients with AMI hospitalized in the Cardiology Department of Kaifeng Central Hospital. Based on carotid ultrasound results, patients were divided into the following two groups: the stable plaque group and the unstable plaque group. Additionally, a control group comprising 380 healthy individuals visiting the hospital's physical examination center during the same timeframe was established. Fasting venous blood samples were collected from all participants to measure blood glucose and triglyceride. The baseline TyG-BMI index was calculated using the formula Ln [fasting triglyceride (mg/dL)×fasting blood glucose (mg/dL)/2]×BMI. The correlation between different plaque groups and the TyG-BMI index was analyzed. The TyG-BMI index was significantly higher in the unstable plaque group compared to the stable plaque group, with values of 252.81±29.99 and 201.92±28.72, respectively (P = 0.034). Spearman's correlation analysis showed a positive correlation between the instability of carotid plaques and the TyG-BMI index in patients with AMI (r = 0.521, P = 0.003). Logistic regression analysis indicated that the TyG-BMI index was an important risk factor for unstable carotid plaques in patients with AMI (OR = 2.691, 95% CI: 1.169-4.123). The findings of this study suggest that an elevated TyG-BMI index significantly increases the risk of unstable carotid plaques in patients with AMI, making it an important risk factor for carotid plaque instability.

Carotid plaque characteristics in the CREST-2 trial

BackgroundThe modest stroke prevention from surgery for asymptomatic carotid disease has prompted a search for predictors that may improve risk stratification beyond luminal stenosis. Plaque disruption and atheroembolization are associated with unique anatomical and histological changes. The Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis Trial (CREST-2) collects information on duplex ultrasound (DUS) plaque biomarkers with the goal of evaluating their relationship to the periprocedural and long-term risks of stroke. In this study, we examine the reliability with which carotid plaque features can be measured from DUS images, and report baseline carotid DUS-derived stenosis and plaque features using semiautomated digital image analysis of patients enrolled in CREST-2. MethodsWe studied the first 503 patients in CREST-2. Patients underwent standardized carotid DUS evaluation pre-enrollment. B-Mode images were scaled linearly to normalize brightness. Plaques were outlined manually. Dedicated software automatically measured the longitudinal sectional area (mm2), grayscale median (GSM), Gray-Weale classification, and tissue composition (mm2) of intraplaque hemorrhage (IPH), lipid, fibrous tissue, muscle, and calcium. We present the mean, standard deviation, median, interquartile range, minimum and maximum range, and proportions of carotid peak systolic velocities (PSVs) and plaque morphological features. We tested for autocorrelation among plaque features and computed the proportion of potentially unstable plaques in the cohort. Reliability of the image analysis techniques was tested in 100 patients using Bland-Altman plots and intraclass and interclass correlation coefficients. ResultsMost patients were male (58.4%), older (mean age of 69.3 years), White (87.5%), and had a PSV of ≥230 cm/s (98.6%); the 1.4% with a PSV of <230 cm/s were enrolled based on catheter angiography. Plaques in this study were large; the mean longitudinal sectional area was 62 ± 37 mm2 (range, 6.2–256.5 mm2). The mean GSM was 58 ± 30 (unitless) (range, 0–168) and Gray-Weale classification was 3.5 ± 0.9 (range, 1–5). The mean areas of tissue types were IPH 5.3 ± 8.9 mm2, lipid 9.3 ± 8.6 mm2, fibrous tissue 10 ± 10 mm2, muscle 17 ± 12 mm2, and calcium 1.6 ± 4.1 mm2. The PSV of patients showed poor correlation with plaque features. The proportion of plaques with a GSM of ≤35 was 22.8%, IPH of ≥5 mm2 was 30.0%, and a lipid-rich necrotic core of ≥40% was 3.0% of the cohort. Plaque measurements could be performed with high reliability with good interobserver and intraobserver correlations. ConclusionsSite-generated, core laboratory-interpreted ultrasound examination provides a reliable way of characterizing carotid plaque morphological features across studies performed at many CREST-2 sites. The initial cohort of patients randomized in CREST-2 had heterogeneity of plaque features despite causing high-grade stenosis. Completion of the trial will provide an opportunity to assess whether plaque heterogeneity interacts with response to revascularization and medical management.

Diagnostics Accuracy of Magnetic Resonance Imaging in Detection of Atherosclerotic Plaque Characteristics in Carotid Arteries Compared to Histology: A Systematic Review.

Carotid plaque composition represents one of the main risk factors of future ischemic stroke. MRI provides excellent soft tissue contrast that can distinguish plaque characteristics. Our objective was to analyze the diagnostic accuracy of MRI imaging in the detection of carotid plaque characteristics compared to histology in patients with symptomatic and asymptomatic carotid atherosclerosis through a systematic review. After prospective registration in PROSPERO (ID CRD42022329690), Medline Ovid, Embase.com, Cochrane Library, and Web of Science Core were searched without any search limitation up to May 27, 2022 to identify eligible articles. Of the 8168 studies, 53 (37 × 1.5 T MRI, 17 × 3 T MRI) evaluated MRI accuracy in the detection of 13 specific carotid plaque characteristics in 169 comparisons. MRI demonstrated high diagnostic accuracy for detection of calcification (3 T MRI: mean sensitivity 92%/mean specificity 90%; 1.5 T MRI: mean sensitivity 81%/mean specificity 91%), fibrous cap (1.5 T: 89%/87%), unstable plaque (1.5 T: 89%/87%), intraplaque hemorrhage (1.5 T: 86%/88%), and lipid-rich necrotic core (1.5 T: 89%/79%). MRI also proved to have a high level of tissue discrimination for the carotid plaque characteristics investigated, allowing potentially for a better risk assessment and follow-up of patients who may benefit from more aggressive treatments. These results emphasize the role of MRI as the first-line imaging modality for comprehensive assessment of carotid plaque morphology, particularly for unstable plaque. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 2.

Reliability Of B-Mode Ultrasound Carotid Plaque Characterization in the CREST-2 Trial

Reliability Of B-Mode Ultrasound Carotid Plaque Characterization in the CREST-2 Trial

Development and Validation of a Fusion Model Based on Carotid Plaques and White Matter Lesion Burden Imaging Characteristics to Evaluate Ischemic Stroke Severity in Symptomatic Patients.

The diagnostic value of carotid plaque characteristics based on higher-resolution vessel wall MRI (HRVW-MRI) combined with white matter lesion (WML) burden for the risk of ischemic stroke is unclear. To combine carotid plaque features and WML burden to construct a hybrid model for evaluating ischemic stroke severity and prognosis in patients with symptomatic carotid artery stenosis. Retrospective. One hundred and ninty-three patients with least one confirmed carotid atherosclerotic stenosis ≥30% and cerebrovascular symptoms within the last 2 weeks (136 in the training cohort and 57 in the test cohort). 3.0T, T2-weighted fluid attenuated inversion recovery (T2-FLAIR) and diffusion-weighted imaging (DWI); HRVW-MRI: 3D T1-weighted variable flip angle fast spin-echo sequences (VISTA), T2-weighted VISTA, simultaneous noncontrast angiography and intraplaque hemorrhage (SNAP), and contrast-enhanced T1-VISTA. The following features of the plaques or vessel wall were assessed by three MRI readers independently: calcification (CA), intraplaque hemorrhage (IPH), lipid-rich necrotic core (LRNC), ulceration, plaque enhancement (PE), maximum vessel diameter (Max VD), maximum wall thickness (Max WT), total vessel area (TVA), lumen area (LA), plaque volume, and lumen stenosis. WMLs were graded visually and categorized as absent-to-mild WMLs (Fazekas score 0-2) or moderate-severe WMLs (Fazekas score 3-6). WML volumes were quantified using a semiautomated volumetric analysis program. Modified Rankin scores (mRS) were assessed at 90 days, following an outpatient interview, or by telephone. LASSO-logistic regression analysis was performed to construct a model. The performance of the model was evaluated using receiver operating characteristic (ROC) curve analyses, calibration curves, decision curve analyses, and clinical imaging curves. Conditional logistic regression analysis was used to explore the associations between the hybrid model-derived score and the modified Rankin Scale (mRS) score at 90 days. The model was constructed using five selected features, including IPH, plaque enhancement, ulceration, NWI, and total Fazekas score in deep WMLs (DWMLs). The hybrid model yielded an area under the curve of 0.92 (95% confidence interval [CI] 0.87-0.97) in the training cohort and 0.88 (0.80-0.96) in the test cohort. Furthermore, the hybrid model-derived score (odds ratio = 1.28; 95% CI 1.06-1.53) was independently associated with the mRS score 90 days after stroke. The hybrid model constructed using MRI plaque characteristics and WML burden has potential to be an effective noninvasive method of assessing ischemic stroke severity. The model-derived score has promising utility in judging neurological function recovery. Stage 2.

Abstract 1155: Symptomatic Low- And High-degree Carotid Stenoses Exhibit Similar Features Of Plaque Instability

Background: Carotid endarterectomy (CEA) for symptomatic carotid stenosis is recommended for patients with the &gt;70% (NASCET) stenosis but not for those with &lt;50%. Since low-degree stenoses may still cause strokes, refined risk stratification is necessary, which could be improved by incorporating biological features of plaque instability. In order to challenge risk-stratification by the degree of stenosis, we compared biological features of carotid plaques from symptomatic patients with &lt;50% stenosis vs. &gt;70% and explored mechanisms behind plaque instability in low-degree stenoses. Methods: CEA specimens were retrieved from symptomatic patients with &gt;70% (n=204) and &lt;50% stenosis (n=34), all part of the Biobank of Karolinska Endarterectomies (BiKE). Patient demographics, plaque morphology from image analyses of preoperative computed tomography angiography (CTA), and RNA-seq analyses of lesions were used for comparisons. Plaque biology was assessed by transcriptomics using principal component analyses (PCA), differential gene expression (DGE)- and gene-set enrichment analyses (GSEA). Immunohistochemistry (IHC) was used to study proteins corresponding to upregulated genes. Results: The demographics of the two groups were statistically similar. They also showed similar plaque morphology with respect to intraplaque hemorrhage (IPH), plaque burden and fibrous cap thickness, whereas calcification was higher in the &lt;50% group and lipid-rich necrotic core higher in the &gt;70% group. PCA analysis indicated poor clustering, while DGE and GSEA identified enrichment of genes and pathways related to tissue hypoxia and angiogenesis in &lt;50% lesions. Corresponding proteins were detected by IHC in neo-vascularized plaque regions. Conclusions: Plaques from symptomatic patients with &lt;50% carotid stenoses exhibit largely similar morphological and biological features as those from &gt;70% stenoses, emphasizing the need for improved stratification of patients for CEA of symptomatic carotid stenosis. However, pathways associating plaque burden, hypoxia and angiogenesis were particularly enriched in low-grade stenosis lesions suggesting mechanisms behind plaque instability and symptoms in patients with both low- and high-degree stenosis.

Deep learning approach for cardiovascular disease risk stratification and survival analysis on a Canadian cohort.

The quantification of carotid plaque has been routinely used to predict cardiovascular risk in cardiovascular disease (CVD) and coronary artery disease (CAD). To determine how well carotid plaque features predict the likelihood of CAD and cardiovascular (CV) events using deep learning (DL) and compare against the machine learning (ML) paradigm. The participants in this study consisted of 459 individuals who had undergone coronary angiography, contrast-enhanced ultrasonography, and focused carotid B-mode ultrasound. Each patient was tracked for thirty days. The measurements on these patients consisted of maximum plaque height (MPH), total plaque area (TPA), carotid intima-media thickness (cIMT), and intraplaque neovascularization (IPN). CAD risk and CV event stratification were performed by applying eight types of DL-based models. Univariate and multivariate analysis was also conducted to predict the most significant risk predictors. The DL's model effectiveness was evaluated by the area-under-the-curve measurement while the CV event prediction was evaluated using the Cox proportional hazard model (CPHM) and compared against the DL-based concordance index (c-index). IPN showed a substantial ability to predict CV events (p < 0.0001). The best DL system improved by 21% (0.929 vs. 0.762) over the best ML system. DL-based CV event prediction showed a ~ 17% increase in DL-based c-index compared to the CPHM (0.86 vs. 0.73). CAD and CV incidents were linked to IPN and carotid imaging characteristics. For survival analysis and CAD prediction, the DL-based system performs superior to ML-based models.

Correlation between Morphological and Hemodynamic Parameters of Carotid Arteries and Cerebral Vasomotor Reactivity.

The function of cerebral small vessels can be assessed using cerebral vasomotor reactivity (VMR). Our aim in this retrospective cross-sectional study was to investigate a correlation between carotid artery stenosis measured through ultrasonographic morphological and hemodynamic parameters and cerebral VMR. A total of 285 patients (125 males; mean age 54) were included. The breath-holding index (BHI) was used to evaluate cerebral VMR. Ultrasonographic carotid artery parameters were collected: the presence and characteristics of carotid plaques, the degree of carotid diameter stenosis, intima-media thickness (IMT), peak systolic velocity (PSV), and end diastolic velocity (EDV). Additionally, hemodynamic parameters of the middle cerebral artery (MCA) were evaluated, including the mean flow velocity (MFV) and pulsatility index (PI). The following was collected from patients' medical histories: age, gender, and vascular risk factors. A negative correlation between the BHI and age (r = -0.242, p < 0.01), BHI and the presence of carotid plaques, BHI and IMT (r = -0.203, p < 0.01), and BHI and the PI of MCA on both sides (r = -0.268, p < 0.01) was found. We found a positive correlation between the BHI in the left MCA and EDV in the left internal carotid artery (r = 0.121, p < 0.05). This study shows the correlation between cerebral VMR and carotid stenosis but indicates a higher influence of morphological parameters on VMR values.

Abstract WP116: Plaque Features and Infarct Pattern in Ischemic Stroke With Bilateral Carotid Artery Atherosclerosis

Objective: to compare the carotid artery plaque characteristics between ipsilateral and contralateral infarct in ischemic stroke with bilateral carotid artery atherosclerosis, and explore the association between plaque characteristics and infarct pattern. Methods: a total of 186 ischemic stroke patients with bilateral carotid artery atherosclerosis were included, carotid artery plaque burden (the degree of stenosis, maximum wall thickness, lumen area, wall area, normalized wall index (NWI=wall area/[lumen area+ wall area]), and eccentricity index), and vulnerability (intraplaque hemorrhage [IPH], calcification, irregular surface, thin or ruptured fibrous cap[TRFC], and lipid-rich necrotic core[LRNC]) were obtained by MR vessel wall imaging, infarct pattern was divided as single and multiple/recurrent infarcts in infarct ipsilateral carotid artery. Ipsilateral and contralateral carotid artery plaque features were compared, then the carotid artery plaque characteristics on the infarct side were correlated with the infarct pattern. Results: the mean age of subjects included was 68 years old, 79.6% of them were male. Compared with contralateral carotid artery plaque, plaque burden at the ipsilateral carotid artery was much heavy, presented with a higher degree of stenosis, smaller lumen area (0.22±0.15 vs. 0.28±0.15), larger wall area (0.50±0.19 vs.0.42±0.17), and higher eccentricity index (0.67±0.13 vs. 0.58±0.23), all p values&lt;0.05. The vulnerable plaques were also more prevalent at ipsilateral infarct, with a high percentage of IPH (47.8% vs. 19.8%), irregular surface (36.3% vs. 17.5%), TRFC (38.5% vs.12.3%), and LRNC (38.1% vs. 15.9%), all p values were &lt;0.05. After adjusting for covariates, the degree of stenosis (OR=1.590, 95% CI 1.048-2.410) and LRNC (OR=0.259, 95% CI 0.087-0.769) were associated with multiple or recurrent infarcts independently. Conclusion: in ischemic stroke with bilateral carotid atherosclerosis, the atherosclerotic plaque burden at ipsilateral infarct was much heavier and more vulnerable. Both lumen stenosis and plaque components were correlated with multiple or recurrent infarcts in this population.

Abstract TP176: Radiological Reporting Frequencies of High-Risk Non-Stenosing Carotid Plaque Features: A Follow-Up Observational Study

Background: High-risk non-stenosing carotid plaque features are emerging as a possible source of embolism in the setting of ESUS. Unless there is a hemodynamically significant stenosis, neuroradiology reports tend to be rarely descriptive of these features. Methods: In our previous study published in September 2022, we analyzed a patient sample drawn from the stroke registry of the HFHS between June 2016 and June 2021. Our results showed a higher incidence of high-risk plaque features including plaque ulceration (19.08% vs 5.26%, p&lt;0.0001), plaque thickness &gt;3mm: (19.08% vs 7.24%, p=0.001), and length &gt;1cm (13.16% vs 5.92%, p=0.0218) ipsilateral to ESUS. In this subsequent study, we utilized the same patient dataset and used CTA reports on EPIC to explore how frequently neuroradiologists had mentioned those features. We utilized Fisher’s exact test to compare the frequencies of reporting each plaque characteristic. Results: We analyzed 152 CTA reports in depth. Our findings indicate that the frequency of reporting plaque ulceration compared to the frequency of reporting plaque calcification was significantly different (8.1% vs 100%, p&lt; 0.00001), this is also noticed with plaque length (4.6%, p&lt; 0.00001) and soft plaques (72.1%, p&lt; 0.00001). Notably, none of the CTA reports had commented on any plaque thickness or the presence of any “high-risk” features when encountering stroke ipsilaterally. Conclusion: When carotid plaques are not causing hemodynamically significant stenosis, neuroradiology reports frequently mention the density of plaques, but unfortunately overlook other characteristics. It is essential to conduct algorithms, scoring systems and prediction models to determine which plaque features are highly associated with embolism. These models should help prioritize the description of these features, alongside commonly reported metrics such as plaque density and the degree of stenosis.

Atherosclerotic plaque features relevant to rupture-risk detected by clinical photon-counting CT ex vivo: a proof-of-concept study

BackgroundTo identify subjects with rupture-prone atherosclerotic plaques before thrombotic events occur is an unmet clinical need. Thus, this proof-of-concept study aims to determine which rupture-prone plaque features can be detected using clinically available photon-counting computed tomography (PCCT).MethodsIn this retrospective study, advanced atherosclerotic plaques (ex vivo, paraffin-embedded) from the Carotid Plaque Imaging Project were scanned by PCCT with reconstructed energy levels (45, 70, 120, 190 keV). Density in HU was measured in 97 regions of interest (ROIs) representing rupture-prone plaque features as demonstrated by histopathology (thrombus, lipid core, necrosis, fibrosis, intraplaque haemorrhage, calcium). The relationship between HU and energy was then assessed using a mixed-effects model for each plaque feature.ResultsPlaques from five men (age 79 ± 8 [mean ± standard deviation]) were included in the study. Comparing differences in coefficients (b1diff) of matched ROIs on plaque images obtained by PCCT and histology confirmed that calcium was distinguishable from all other analysed features. Of greater novelty, additional rupture-prone plaque features proved discernible from each other, particularly when comparing haemorrhage with fibrous cap (p = 0.017), lipids (p = 0.003) and necrosis (p = 0.004) and thrombus compared to fibrosis (p = 0.048), fibrous cap (p = 0.028), lipids (p = 0.015) and necrosis (p = 0.017).ConclusionsClinically available PCCT detects not only calcification, but also other rupture-prone features of human carotid plaques ex vivo.Relevance statementImproved atherosclerotic plaque characterisation by photon-counting CT provides the ability to distinguish not only calcium, but also rupture-prone plaque features such as haemorrhage and thrombus. This may potentially improve monitoring and risk stratification of atherosclerotic patients in order to prevent strokes.Key points• CT of atherosclerotic plaques mainly detects calcium.• Many components, such as intra-plaque haemorrhage and lipids, determine increased plaque rupture risk.• Ex vivo carotid plaque photon-counting CT distinguishes haemorrhage and thrombus.• Improved plaque photon-counting CT evaluation may refine risk stratification accuracy to prevent strokes.Graphical

Thin Calcification Predicts Lipid Component in Carotid Plaque—Relationship Between Lipid Distribution and Thin Calcification

BackgroundAccurately evaluating plaque characteristics is essential because lesions with lipid-rich plaque put patients at risk of thromboembolic complications from carotid artery stenting (CAS). Near-infrared spectroscopy (NIRS) is a diagnostic imaging modality that identifies lipid components from the near-infrared absorption pattern, but does not reveal the distribution of calcification. The purpose of this study was to investigate the calcification characteristics of unstable carotid plaques, focusing on relationships between the calcification characteristics revealed by computed tomography angiography (CTA) and the lipid core distribution derived from NIRS. MethodsParticipants in this retrospective analysis comprised 35 patients (29 men, 6 women; mean age, 76.0 years; range, 52–89 years) who underwent CAS in our institute between January 2021 and December 2022. We evaluated the thickness and length of carotid calcifications at the minimal lumen level from preoperative CTA and analyzed the relationship with maximal lipid core burden index (max-LCBI) from NIRS. ResultsStrong, negative linear correlations were observed between the thickness of calcification and max-LCBI at Area (any segment in a target lesion) (r=-0.795, p<0.001), max-LCBI at minimal lumen area (MLA) (r=-0.795, p<0.001) and LCBI at Lesion (rate of LCBI in entire plaque lesion) (r=-0.788, p<0.001), respectively. Significant negative linear correlations were observed between distribution of calcification length and max-LCBI at Area (r=-0.429, p=0.01), max-LCBI at MLA (r=-0.373, p=0.027) and LCBI at Lesion (r=-0.443, p=0.008). ConclusionsThin and ubiquitous carotid calcification was associated with LCBI values derived from NIRS indicative of carotid lipid plaque distribution, implying the possibility of predicting lesion instability.

Noninvasive carotid ultrasound for predicting vulnerable plaques of the coronary artery based on optical coherence tomography images.

The risk factors for coronary and carotid plaque development are consistent. Coronary plaque rupture is a major cause of adverse cardiovascular events. Ultrasound can evaluate vulnerable carotid plaques and provide information for predicting vulnerable coronary plaques identified by optical coherence tomography (OCT). This study aimed to investigate the predictive role of non-invasive carotid ultrasound in OCT diagnosis of atherosclerotic vulnerable plaque. A total of 70 participants, including 35 patients with and 35 without vulnerable coronary plaque, were enrolled in this case-control study at Beijing Anzhen Hospital from 2016 to 2021. The data of 70 patients with suspected coronary heart disease who had undergone OCT examination during percutaneous coronary intervention (PCI) surgery and completed carotid ultrasound examination within 3 days before PCI were analyzed retrospectively. According to the OCT diagnostic criteria for vulnerable plaques, the patients were divided into the vulnerable-plaque group and the stable-plaque group. Univariate and binary logistic regression analyses assessed risk factors for vulnerable coronary plaque. Receiver operating characteristic (ROC) curve analysis was used to determine the predictive power of carotid plaque features. The univariate analysis demonstrated that the differences in high-sensitivity C-reactive protein levels and carotid plaque characteristics (irregular fibrous cap, heterogeneous plaque, hypoechoic plaque, plaque calcification, and a plaque thickness of greater than 3 mm) between the two groups were statistically significant. The logistic multivariate regression analysis revealed that an irregular fibrous cap of a carotid plaque [odds ratio (OR) =4.819; 95% confidence interval (CI): 1.106-22.867; P=0.048] and a hypoechoic plaque (OR =9.632; 95% CI: 2.138-43.384; P<0.05) were independent risk factors for predicting vulnerable plaques of the coronary artery. Noninvasive carotid ultrasound is feasible and clinically valuable for predicting vulnerable and asymptomatic coronary plaques defined by OCT. With this method, adverse events can be diagnosed and treated in advance.

Modern approaches to ultrasonographic assessment of carotid plaque in terms of its potential instability.

Aim: To identify potentially adverse characteristics of atherosclerotic carotid plaque in terms of stroke risk. Materials and Methods: The study is based on the analysis of US data obtained from 96 patients aged 47 to 84 years diagnosed with carotid stenosis. The patients were divided into 2 groups depending on the presence or absence of ischemic events. Examination methods: clinical, duplex US, brain MRI, statistical. In addition to the standard US criteria for the evaluation of carotid stenoses, superb microvascular imaging (SMI) and shear wave elastography (SWE) are used. Results: Statistically significant association of the following characteristics of plaques with the presence of ipsilateral ischemia focus was established: maximum thickness (p = 0,04), presence of microvascularization according to SMI data (p = 0,02), degree of carotid stenosis (statistically significant in the right carotid circulation [p = 0,04]), stiffness of the plaque according to SWE data (significantly in the right carotid circulation [p = 0,001]), type of plaque echogenicity according to Gray-Weale-Geroulakos classification (on the right carotid artery; p = 0,04). Conclusions: The presence of microvascularization according to SMI data and the low stiffness of the plaque according to SWE data can characterize the potential instability of the carotid plaque. These criteria should be added to the traditional US assessment of carotid plaques.

Identification of symptomatic carotid artery plaque: a predictive model combining angiography with optical coherence tomography.

Symptomatic carotid artery disease is indicative of an elevated likelihood of experiencing a subsequent stroke, with the morphology of plaque and its specific features being closely linked to the risk of stroke occurrence. Our study based on the characteristics of carotid plaque assessed by optical coherence tomography (OCT), the plaque morphology evaluated by digital subtraction angiography (DSA) and clinical laboratory indicators were combined, develop a combined predictive model to identify symptomatic carotid plaque. Patients diagnosed with carotid atherosclerotic stenosis who underwent whole-brain DSA and OCT examination at the Affiliated Hospital of Jining Medical University from January 2021 to November 2023 were evaluated. Clinical features, as well as DSA and OCT plaque characteristics, were analyzed for differences between symptomatic and asymptomatic cohorts. An analysis of logistic regression was carried out to identify factors associated with the presence of symptomatic carotid plaque. A multivariate binary logistic regression equation was established with the odds ratio (OR) serving as the risk assessment parameter. The receiver operating characteristic curve was utilized to assess the combined predictive model and independent influencing factors. A total of 52 patients were included in the study (symptomatic: 44.2%, asymptomatic: 55.8%). Symptomatic carotid stenosis was significantly linked to four main factors: low-density lipoprotein-cholesterol >3.36 mmol/L [OR, 6.400; 95% confidence interval (CI), 1.067-38.402; p = 0.042], irregular plaque (OR, 6.054; 95% CI, 1.016-36.083; p = 0.048), ruptured plaque (OR, 6.077; 95% CI, 1.046-35.298; p = 0.048), and thrombus (OR, 6.773; 95% CI, 1.194-38.433; p = 0.044). The combined predictive model generated using four indicators showed good discrimination (Area Under Curve, 0.924; 95% CI, 0.815-0. 979). The p value was <0.05 with 78.26% sensitivity and 93.10% specificity. OCT is valuable in evaluating the plaque characteristics of carotid atherosclerotic stenosis. The combined predictive model comprising low-density lipoprotein-cholesterol >3.36 mmol/L, irregular plaque, ruptured plaque, and thrombus could help in the detection of symptomatic carotid plaque. Further research conducted on additional independent cohorts is necessary to confirm the clinical significance of the predictive model for symptomatic carotid plaque.

Carotid plaque score and ischemic stroke risk stratification through a combination of B-mode and contrast-enhanced ultrasound in patients with low and intermediate carotid stenosis.

The occurrence of ischemic stroke (IS) is closely related to the characteristics of carotid plaque (CP). Due to the effect of stroke risk stratification based on B-mode ultrasound (US) and contrast-enhanced ultrasound (CEUS) that has not been studied in patients with low and intermediate carotid stenosis, we construct and validate a CP score and ischemic stroke risk stratification (ISRS) using a combination of B-mode and CEUS, in order to provide new convenient strategies to stratify these patients to prevent stroke. This retrospective study evaluated 705 patients with low and intermediate carotid stenosis who underwent B-mode and CEUS from November 2021 to April 2023. Qualitative B-mode and CEUS features of carotid plaques were analyzed using a univariable and multivariable logistic regression to construct the CP score. Then, we combined the CP score with Essen stroke risk score (ESRS) to develop ISRS. This study included a total of 705 patients with low and intermediate carotid stenosis, of which 394 were symptomatic patients (with a mean age of 71.03 ± 10.48 years) and 311 were asymptomatic patients (with a mean age of 65.13 ± 10.31 years). Plaque echogenicity, plaque morphology, carotid intima-media thickness in B-mode US and intraplaque neovascularization grading and perfusion pattern in CEUS were significantly associated with IS. The ISRS incorporating these five predictors and ESRS showed good discrimination and calibration in both primary cohort [area under the curve (AUC), 0.91; Hosmer-Lemeshow test, p = 0.903] and validation cohort (AUC, 0.84; Hosmer-Lemeshow test, p = 0.886). We developed an effective and practical tool to identify and stratify patients with low and intermediate carotid stenosis, based on the CP score and ISRS estimation. Our study may provide new insights into managing patients with no indication of surgery.

Pericarotid adipose tissue computed tomography attenuation distinguishes different stages of carotid atherosclerotic disease: a cross-sectional study.

Carotid atherosclerotic plaque inflammation plays a critical role in guiding the prevention of secondary stroke. Increased perivascular adipose tissue attenuation observed on computed tomography angiography (CTA) may indicate local inflammation. Our objective was to investigate whether pericarotid adipose tissue (PCAT), as a local inflammation biomarker, could distinguish between different stages of carotid atherosclerotic disease plaques. We prospectively enrolled 45 consecutive acute stroke patients with carotid artery stenosis from September 2019 to September 2021. We then matched them to non-stroke patients (n=67) and no carotid atherosclerotic disease controls (n=65) based on gender, age, and cardiovascular risk factors. We compared PCAT attenuation, carotid plaque features on CTA, clinical risk factors, and serum inflammatory factors across the different groups. To detect the association of PCAT attenuation with stage of carotid atherosclerotic disease, we used multivariable logistic regression analysis. Patients with acute stroke had a higher PCAT attenuation (-78.80±11.62 HU) than patients with non-stroke (-89.01±10.81 HU, P<0.001) and no carotid atherosclerotic disease controls (-95.24±10.81 HU, P<0.001). PCAT attenuation was significantly increased in non-stroke patients compared to non-stroke patients over no carotid atherosclerotic disease controls (P=0.004). The association between PCAT attenuation and the stage of carotid atherosclerotic disease was independent of age, gender, cardiovascular risk factors, and CTA plaque characteristics. No interaction was observed between clinical features and CTA plaque characteristics on PCAT attenuation. PCAT attenuation, which is an imaging biomarker of local inflammation, independently distinguishes patients with different stages of carotid atherosclerotic disease. Quantitative evaluation of PCAT attenuation in carotid atherosclerotic disease is expected to guide targeted surgical treatment of carotid plaque.

Investigating the Association of Carotid Atherosclerotic Plaque MRI Features and Silent Stroke After Carotid Endarterectomy.

The predictive value of carotid plaque characteristics for silent stroke (SS) after carotid endarterectomy (CEA) is unclear. To investigate the associations between carotid plaque characteristics and postoperative SS in patients undergoing CEA. Prospective. One hundred fifty-three patients (mean age: 65.4 ± 7.9 years; 126 males) with unilateral moderate-to-severe carotid stenosis (evaluated by CT angiography) referred for CEA. 3 T, brain-MRI:T2-PROPELLER, T1-/T2-FLAIR, diffusion weighted imaging (DWI) and T2*, carotid-MRI:black-blood T1-/T2W, 3D TOF, Simultaneous Non-contrast Angiography intraplaque hemorrhage. Patients underwent carotid-MRI within 1-week before CEA, and brain-MRI within 48-hours pre-/post-CEA. The presence and size (volume, maximum-area-percentage) of carotid lipid-rich necrotic core (LRNC), intraplaque hemorrhage (Type-I/Type-II IPH) and calcification were evaluated on carotid-MR images. Postoperative SS was assessed from pre-/post-CEA brain DWI. Patients were divided into moderate-carotid-stenosis (50%-69%) and severe-carotid-stenosis (70%-99%) groups and the associations between carotid plaque characteristics and SS were analyzed. Independent t test, Mann-Whitney U-test, chi-square test and logistic regressions (OR: odds ratio, CI: confidence interval). P value <0.05 was considered statistically significant. SS was found in 8 (16.3%) of the 49 patients with moderate-carotid-stenosis and 21 (20.2%) of the 104 patients with severe-carotid-stenosis. In patients with severe-carotid-stenosis, those with SS had significantly higher IPH (66.7% vs. 39.8%) and Type-I IPH (66.7% vs. 38.6%) than those without. The presence of IPH (OR 3.030, 95% CI 1.106-8.305) and Type-I IPH (OR 3.187, 95% CI 1.162-8.745) was significantly associated with SS. After adjustment, the associations of SS with presence of IPH (OR 3.294, 95% CI 1.122-9.669) and Type-I IPH (OR 3.633, 95% CI 1.216-10.859) remained significant. Moreover, the volume of Type-II IPH (OR 1.014, 95% CI 1.001-1.028), and maximum-area-percentage of Type-II IPH (OR 1.070, 95% CI 1.002-1.142) and LRNC (OR 1.030, 95% CI 1.000-1.061) were significantly associated with SS after adjustment. No significant (P range: 0.203-0.980) associations were found between carotid plaque characteristics and SS in patients with moderate-carotid-stenosis. In patients with unilateral severe-carotid-stenosis, carotid vulnerable plaque MR features, particularly presence and size of IPH, might be effective predictors for SS after CEA. 2 TECHNICAL EFFICACY: Stage 2.

Abstract 17231: Importance of Intra Plaque Hemorrhage During Carotid Artery Revascularization

Introduction: The American Heart Association currently estimates that every 3 minutes a person dies from a stroke. Carotid artery stenosis, a major risk factor for new and recurrent strokes, can be treated with carotid artery revascularization. Vascular emboli released during this procedure are non-invasively detected by transcranial doppler (TCD) ultrasound as micro embolic signals (MES). In this study we aim to show the relationship between carotid plaque characteristics and MES rates that were detected by TCD-monitoring throughout the stages of the carotid artery revascularization procedures. Methods: Before elective carotid revascularization 30 patients (mean age 72±8 years; 16 males, 14 females) underwent 3-T MRI. After localization of the carotid bifurcation using phase contrast imaging, Time-of-Flight, 3D T1 weighting, transverse T1 and T2 weightings and proton density sequences were acquired. The different plaque components: lipid core, intraplaque hemorrhage, calcification and the characterization of the fibrous cap were assessed. While 20 patients underwent carotid endarterectomy (CEA), 10 patients had carotid artery stenting (CAS). CES was divided into 9 stages: 1- Pre-procedure, 2- Dissection, 3- IC clamp, 4- Shunt placement, 5- Shunt open, 6- Endarterectomy, 7- Clamped, 8- IC opened, 9- Post-procedure. Similarly, CAS was divided into 9 stages: 1- Pre-procedure, 2- Arch-carotid angiography, 3- Wire insertion, 4- Filter deployment, 5- Pre-dilation, 6- Stent deployment, 7- Post-dilation, 8- Final angiography, 9- Post-procedure. Patients were monitored continuously with TCD to detect pre-procedural, intra-procedural and post-procedural MES rates. Results: Intraplaque hemorrhage was observed in 18 patients (60%). Patients with intra plaque hemorrhage had more MES during carotid artery dissection/arch-carotid angiography (p=0.028) and IC clamping/wire insertion (p=0.009) compared to patients without intra plaque hemorrhage in the pre-procedural stage. Conclusions: Carotid plaques with intra plaque hemorrhage is associated with higher MES during carotid artery revascularization procedures.